A structural-functional assessment of serum albumin in cancerous diseases

HSA structure was studied in healthy subjects and cancer patients using infrared spectroscopy. No significant differences were observed although the intensity of valent C-H fluctuation lines in alkyl groups of HSA was slightly increased in cancer patients. Gas-liquid chromatography established changes in the profile of polyunsaturated fatty acids binding to HSA in cancer patients. The data obtained suggest inhibition of omega-6 pathway of fatty acid metabolism and activation of omega-3 pathway. Marked binding of POL products to serum albumin was found nonspecific and was considered evidence of protective function of that protein.     

Expression of cyclooxygenase-2 and DNA topoisomerase II alpha in precancerous and cancerous lesions of the oral mucosa

The involvement of cyclooxygenase (COX)-2 in oral carcinogenesis and outcome of the patients is not fully understood. To determine whether COX-2 expression could serve as an indicator for them, we examined the expression of COX-2 and DNA topoisomerase (DNA-Topo) II alpha as an index of cell proliferating activity in precancerous and cancerous lesions of the oral mucosa. A 164 samples composed of 60 intraepithelial dysplasias (IEDs), 12 carcinomas in situ (CISs), 72 squamous cell carcinomas (SCCs) including 12 early invasive SCCs, 10 undifferentiated carcinomas (UCs), and 10 epithelial hyperplasias (EHPs) in the oral mucosa were examined immunohistochemically for COX-2 and DNA-Topo II alpha. Normal squamous epithelium as the control showed no COX-2 expression, whereas 41% of IEDs, 67% of CISs, 74% of SCCs, and 86% of UCs demonstrated increased COX-2 expression with elevated DNA-Topo II alpha labeling index (LI). High COX-2 expression was also observed in 61% of EHPs, but DNA-Topo II alpha LI was very low. Increased expression of COX-2 protein correlated with elevated DNA-Topo II alpha LI, indicating that COX-2 may contribute to malignant transformation and tumor growth. These two enzyme activities were increased as T, N, and M categories and stages proceeded. The patients with high expression of both COX-2 and DNA-Topo II alpha showed poor prognosis. Our results suggested that COX-2 expression become a possible indicator in oral carcinogenesis and may reflect the outcome of the patients.     

Nucleolar organizer regions in precancerous and cancerous lesions of the bronchus

Using a silver staining technique, nucleolar organizer region-associated proteins (Ag-NOR) were studied in paraffin sections of five specimens of normal bronchial epithelium, eight of atypical squamous metaplasia, five of carcinoma in situ, and seven of microinvasive squamous cell carcinoma. The mean number of Ag-NOR in the nucleus were normal epithelium 1.2 +/- 0.1 (mean +/- SD), atypical squamous metaplasia (borderline lesion) 2.2 +/- 0.5, carcinoma in situ 3.8 +/- 0.6, and microinvasive squamous cell carcinoma 4.8 +/- 1.1. There was a highly significant difference between the Ag-NOR numbers in the atypical squamous metaplasia and those in the carcinoma in situ (P less than 0.01). The Ag-NOR staining is a useful technique for the differential diagnosis of difficult borderline lesions in the bronchial epithelium.     

Interphase-FISH examinations in paraffin sections from benign, precancerous, and cancerous lesions of the skin and oral mucosa

In a preliminary pilot study centromeric probes for chromosomes #7, #8, #11, and #17 and two-colour-FISH were applied on interphase nuclei of 10 coded histologic thin sections obtained from archival paraffin material from precancerous lesions and malignant tumors of the mouth epithelium. Brilliant signals could be obtained in this material without any computerized processing. Among the ten coded probes, localized malignant areas within grade 2 leukoplakias could be detected by their increased number of aneusomic cells, as could the samples from carcinomas. In extension of this study archival paraffin material from 30 epithelial tumors of the skin were examined. The studied squamous cell and Bowen carcinomas were characterized by a large number of chromosomally aberrant subclones and gains of chromosomes were the prevailing finding. In contrast, keratoacanthomas showed distinctly less clonal variation, their majority exhibiting small, but significant clones with chromosome loss, particularly of chromosome #7, less distinctly of chromosome #17.     

MGMT expression in oral precancerous and cancerous lesions: correlation with progression, nodal metastasis and poor prognosis

Alkylation of DNA at the O(6) position of guanine is a critical step in the induction of mutations by carcinogenic and chemotherapeutic alkylating agents. O(6)-methylguanine-DNA methyltransferase (MGMT) is an enzyme that removes mutagenic adducts from the O(6) position of guanine, thereby protecting the genome against guanine to adenine transitions. We hypothesized that alteration in MGMT expression might occur in early stages of development of oral cancer and be associated with disease progression. Immunohistochemical analysis of MGMT expression was carried out in 107 oral squamous cell carcinomas (OSCCs), 78 oral precancerous lesions (OPLs) (58 hyperplasias and 20 dysplasias) and 30 histologically normal oral tissues and correlated with clinicopathological parameters as well as major risk factors. Decreased MGMT expression was observed as early as in hyperplasia (p=0.003; Odd's Ratio (OR)=5.0). Significant loss of MGMT expression was observed from hyperplasia to dysplasia (p=0.034; OR=4.0). Loss of MGMT expression was associated with late clinical stage of OSCCs (p=0.027, OR=2.0) and nodal metastasis (p=0.031, OR=2.5). Decreased MGMT expression was associated with smokeless tobacco (ST) consumption in patients with OPLs (p=0.017, OR=3.6) and OSCCs (p=0.031, OR=2.8). Significant association was also observed between loss of MGMT expression and poor prognosis of OSCC patients (p=0.02; OR=5.2). The decreased MGMT expression in OPLs suggested that deregulation of MGMT expression is an early event in the development of oral cancer. In OSCCs, its correlation with late clinical stage, and nodal metastasis suggests association with aggressive tumor behavior and cancer progression, underscoring its potential as a candidate predictive marker for nodal metastasis and disease prognosis. Correlation of loss of MGMT expression with ST consumption underscored its significance in ST-associated oral carcinogenesis.     

ras蛋白在食管癌及食管癌前病变组织中的表达

目的了解中国食管癌高发区食管癌变发生过程中癌基因ｒａｓ的变化。方法采用卵白素－生物素－辣根过氧化氢酶复合物（ＡＢＣ）方法测定食管癌高发区食管癌及癌前病变组织中癌基因ｒａｓ蛋白的表达状况。结果在正常食管上皮和癌前病变组织中未见ｒａｓ蛋白表达,而３６例食管癌组织有９例出现免疫阳性反应,其免疫阳性反应率为２５％。结论ｒａｓ癌基因表达是食管癌变晚期阶段的一个分子学变化。     

Selenium therapy in patients with precancerous and malignant oral cavity lesions: preliminary results.

Baseline selenium (Se) levels in serum samples were collected from 22 patients with precancerous and 19 with malignant oral cavity lesions as well as from 13 healthy controls of the same geographic areas. Mean serum Se levels were 105, 101, and 77.03 ng/ml in the precancerous, controls, and malignancy groups, respectively. A statistically significant difference (p less than 0.005) was found between the neoplastic and both the precancerous and control groups. After careful clinical evaluation, precancerous patients received three 4-week cycles of Se, in either inorganic or organic form. Of the 22 precancerous patients entering the study, 18 were available for evaluation of clinical response. The analysis of serum Se variations revealed that serum Se levels tended to increase after the first and second cycles and then gradually returned to baseline values. At the end of the therapy, there were two complete responses (CR), five partial responses (PR), six minor responses (MR), and five stable diseases (SD) with an objective response (CR + PR) of 38.8%. Progression after suspension of therapy occurred in 7 of 18 patients; this may indicate the need of a longer treatment period with this essential trace element.     

肺癌及癌前病变组织芯片中PTEN的表达及其意义

目的检测肺癌组织中PTEN蛋白的表达,并探讨其在肺癌发生、发展中的作用和意义。方法利用组织芯片技术和免疫组化方法,检测原发性肺癌89例、淋巴结转移性肺癌12例、癌前病变12例和正常肺标本10例中PTEN蛋白的表达情况。结果原发性肺癌中PTEN阳性率为44.9%,显著低于正常组(90.0%)(P<0.05);PTEN的表达与分化程度、淋巴结转移和临床分期相关(P<0.05)。结论PTEN蛋白在肺癌中的表达阳性率降低,并且与病情进展程度相关,PTEN的失活促进了肿瘤的发生和发展,与预后不良相关。     

Clinical significance of altered expression of retinoid receptors in oral precancerous and cancerous lesions: relationship with cell cycle regulators

Alterations in expression of retinoid receptors are implicated in human cancers. We hypothesized that altered expression of retinoic acid receptors (RARalpha,beta,gamma) and retinoid X receptor RXRalpha and their relationship with cell cycle regulators (p53, p16, p21) is associated with development, progression and prognosis of oral cancer. Immunohistochemical analysis of RAR alpha, beta, gamma and RXRalpha proteins was carried out on serial sections from 244 oral squamous cell carcinomas (OSCCs), 102 potentially malignant lesions (65 hyperplasias, 37 dysplasias), 83 matched histologically normal oral tissues and 29 normal mucosa from non-exposed individuals without oral lesions and correlated with expression of cell cycle regulators p53, p16 and p21 as well as with clinicopathological parameters. Expression of retinoid receptors RARbeta, RARgamma, RXRalpha and cell cycle regulators p16 and p21 was decreased in majority of oral SCCs as well as in potentially malignant lesions. Multivariate stepwise logistic regression analysis carried out for comparison of non-exposed normal oral mucosa with histologically normal oral tissues from patients with oral lesions showed significant loss of RARbeta or p53 accumulation (RARbeta(-)/p53(+) Odd's ratio, OR = 266.6, p = 0.000); non-exposed normal mucosa from individuals without oral lesions with potentially malignant lesion was RARbeta(-)/p21(-)/p53(+) (OR = 215.7, p = 0.000); matched normal to potentially malignant stage was RARalpha(+)/p21(-) (OR = 4.414, p = 0.005); hyperplasia to dysplasia was RARalpha(+)/p53(+) (OR = 4.72, p = 0.005) and potentially malignant to malignant phenotype was RARalpha(+) (OR = 2.061, p = 0.004). The prognostic relevance of these factors was assessed in 115 of these SCC patients who were followed-up for a maximum period of 94 months (median 21 months). Multivariate analysis using Cox's proportional Hazard's model showed that RARalpha(+)/p21(-) phenotype was associated with shorter disease-free survival (Hazard's ratio, HR = 1.863, p = 0.0471). To our knowledge, this is the first large study showing alterations in expression of retinoid receptors at the protein level at different stages in development and progression of oral SCC. It also underscored the prognostic significance of retinoid receptors and their interactions with cell cycle regulators in multistep oral tumorigenesis.     

食管和贲门癌及癌前病变患者血清中多个自身抗体的检测及其临床意义

目的:探讨食管和贲门癌及癌前病变患者血清中多个肿瘤相关自身抗体的变化特征及其在食管和贲门癌高危人群筛查和早期诊断中的意义。方法:应用间接酶联免疫反应法和肿瘤相关抗原微阵列(包含8个重组的癌抗原蛋白:C-myc、p53、cyclinB1、p16、p62、Koc、IMP1和Survivin)检测376例食管和贲门各级病变患者(正常、癌前病变和癌)血清中的自身抗体。结果:在所检测的八种抗原中,p53、C-myc、cyclinB1、IMP1和p62从正常食管到癌前病变及癌患者血清中和p53、C-myc、p16、p62在正常贲门到癌前病变及癌患者血清中阳性百分率均具有线性升高趋势。单一抗体对食管和贲门癌检出率较低,p53在癌血清中的表达阳性率在所有抗原中最高,在食管癌和贲门癌患者中分别为23%(13/57)和21%(9/43)。但是,当应用8个抗原分析时,至少有1个反应为阳性时,其检出阳性率明显增高,食管和贲门癌的阳性检出率分别提高到63%(36/57)和61%(26/43),上述检测指标在正常食管和贲门与相应各级癌前病变和癌患者阳性表达率差异有统计学意义,P<0·05。结论:联合应用多个肿瘤相关抗原比应用单个肿瘤相关抗原分析食管和贲门癌及癌前病变患者血清中的自身抗体变化能够提高癌和癌前病变患者的检出率。食管和贲门癌多个相关抗原微阵列的进一步优化有可能成为临床上食管和贲门癌和高危人群检测和早期诊断的非侵袭性方法。     

Heteromorphisms of C-bands in patients with precancerous and cancerous lesions of the cervix uteri

C-band heteromorphisms of chromosomes 1, 9 and 16 were studied in 62 patients with cervical cancer, 100 women with various grades of precancerous lesions and 47 normal women as controls. The data showed an increased frequency of heteromorphisms of chromosome 1 in patients with cancer (48.39%) and severe dysplasias (40%) as compared to controls (29.8%) and lower grades of dysplastic lesions, i.e. mild and moderate (28.8%). The increase in the incidence of chromosome 1 heteromorphisms in cancer was found to be statistically significant (p less than 0.05) compared to controls. The present study indicates that C-band heteromorphisms may play some role in the development of malignancy of the uterine cervix.     

VEGF in the culture of PMN and the serum in oral cavity cancer patients

Vascular endothelial growth factor (VEGF) is a multifunctional cytokine that plays a pivotal role in angiogenesis in vivo. In the present study we examined the ability of polymorphonuclear neutrophils (PMN) to secrete VEGF confronted with the serum levels in oral cavity cancer patients. To investigate whether VEGF may have a prognostic importance, its value in the serum and the culture supernatants was related to the clinical course of patients. The levels of VEGF in the culture supernatant of PMN from patients were significantly higher than those from control. Increased VEGF production by PMN according to clinical progression disease, observed in the present study, seems to suggest a stimulating role of tumour cells in VEGF production by PMN. Additionally, a decrease in the ability of PMN to VEGF release after surgery may be caused by a removal of the tumour mass and then the lack the effects of tumour cells on PMN function. Results obtained appear to suggest that PMN can contribute significantly to the initiation and amplification of tumour angiogenesis and metastasis in oral cavity cancer patients. Increased values of VEGF with progression of disease and decreased values after surgery treatment clearly suggest that VEGF can play a role as a tumour marker in oral cavity cancer patients.     

Tissue carcinoembryonic antigen and DNA aneuploidy in precancerous and cancerous colorectal lesions

Chronic inflammatory bowel disease (CIBD) and colorectal adenoma are considered as precancerous conditions and lesions of large bowel carcinoma, respectively. They, therefore, may be used to study the behavior of such different factors as tumor-associated antigens and nuclear DNA content abnormalities in colorectal carcinogenesis. Tissue concentrations of carcinoembryonic antigen (CEA) were significantly higher in those precancerous lesions (CIBD: 61 +/- 11.2 ng/mg, adenoma: 70 +/- 6 ng/mg; mean +/- standard error of the mean) than in normal colonic mucosa (36 +/- 4.7 ng/mg). Colorectal carcinoma had still higher tissue levels (437 +/- 108.2 ng/mg). No correlation between tissue CEA and tumor differentiation could be found, but there was a significant difference between aneuploid (747 +/- 354 ng/mg) and diploid (139 +/- 43 ng/mg) tumors. Using flow cytometry DNA aneuploidy was present in 31.6%, 10.5%, and 51.6% of CIBD, colorectal adenoma, and carcinoma, respectively. These data suggest that the occurrence of aneuploidy is not strongly dependent on a malignant transformation, but it may also be present in premalignant colorectal lesions without cellular dysplasia.     

Clinical significance of serum levels of SCC antigen in cancers of the oral cavity

The serum levels of SCC antigen were investigated both in 157 patients with oral squamous cell carcinomas and in 28 patients with oral benign diseases as control. The cut off level could be determined to be 1.71 ng/ml with the mean level of control group plus twice standard deviation. There was a significant correlation between the serum levels and clinical findings of oral carcinomas: the antigen levels closely correlated with the changes of tumor volume and clinical stages in squamous cell carcinoma patients. However, there was no relationship between tumor differentiation and SCC antigen levels. It appeared that higher serum levels of SCC antigen were found in patients with carcinomas of the maxilla and floor of the mouth than in that of other regions. As the serum levels of SCC antigen have increased in the follow-up patients, even if lower than the cut off level, they often suggest the relapses of malignant tumor.